The risk of aortic dissection in women with Turner syndrome

Preimplantation genetic testing for aneuploidy in patients with partial X monosomy using their own oocytes: is this a suitable indication?

OBJECTIVE

To describe the outcome of preimplantation genetic testing (PGT-A) using their own oocytes in patients with mosaic Turner Syndrome (MTS). The impact of the assisted reproduction technique (ART) performed (PGT-A or oocyte donation) and the type of absence of the X chromosome (total or partial) were considered.

DESIGN

Retrospective observational multicenter study.

SETTING

University-affiliated private in vitro fertilization center.

PATIENT(S)

Fifty-six patients with MTS with whom 65 ovarian stimulation cycles for PGT-A (fluorescence in situ hybridization/arrays-next generation sequencing) were performed. The study included 90 women with MTS and 20 women with pure Turner Syndrome (PTS) who underwent 140 and 25 oocyte donation (OD) cycles, respectively.

INTERVENTION(S)

In vitro fertilization for PGT-A (fluorescence in situ hybridization/arrays-next generation sequencing) or OD.

MAIN OUTCOME MEASURE (S)

Reproductive outcome and feto-maternal outcomes.

RESULTS

The live birth rate (LBR) per embryo transfer in patients with MTS tended to be higher in OD 37.7% (95% confidence interval [CI]: 29.3-46.1) than that observed for PGT-A 22.5% (95% CI 7.8-38.2), and the cumulative LBR (CLBR), with 77.6% vs. 43.3%, respectively. Likewise, the LBR per patient was significant when comparing PGT-A vs. OD, with 12.5% (95 CI 3.9-21.1) vs. 51.1% (40.7-61.4), respectively. While focusing on the X chromosome, partial MTS (PTS), we found significant differences in the CLBR per embryo transfer, with 77.6% vs. 29.2%, and also in the LBR per patient: 51.1% (40.7-61.4) in MTS vs. 15% (95 CI 0.0-30.1) in PTS.

CONCLUSION(S)

Oocyte donation is the best reproductive option in females with Turner Syndrome with or without mosaicisms. Nevertheless, PGT-A is a valid therapeutic option in patients with MTS using their own oocytes, and OD should not necessarily be directly recommended.

[Procreation in Turner's syndrome: which recommendations before, during and after pregnancy?]

Turner's Syndrome (TS) is characterized by an ovarian failure which occurs in most cases before puberty and leads to infertility. In less than 10% of women with TS, puberty may occur and spontaneous pregnancies are possible with a high risk of fetal loss, chromosomal and congenital abnormalities. Fertile women with TS should therefore be counselled with regard to these increased risks and be offered prenatal diagnosis testing. For all the other women with TS, in vitro fertilization with oocyte donation (OD) has dramatically transformed the prognosis of infertility. However, in the same time, it has become obvious that pregnancies in TS either spontaneous or obtained after oocyte donation are at very high risk of possible sudden death. Miscarriages are very frequent probably linked to uterine abnormalities. The most specific risks lie in cardiovascular complications involving aortic root dissection, severe hypertension (HTA) or ventricular insufficiency. In fact pregnancies in TS women cumulate the risk of congenital heart defects and HTA associated to TS, the risk of preeclampsia associated to oocyte donation and the increased cardiac work necessary for pregnancy. It is therefore absolutely necessary for all women with TS to undergo a full cardiological assessment before seeking to become pregnant including echocardiography, thoracic magnetic resonance imaging (MRI) to verify aortic root, cardiac valves and left ventricular function, hypertension monitoring and treatment. Single embryo transfer must definitively be considered. Cardiovascular surveillance during pregnancy has to be enhanced especially at the third trimester and during the peripartum period, most women requiring caesarean section for delivery because of cephalopelvic disproportion and/or aortic root dilatation risk.

[Oocyte donation in Turner syndrome]

Turner syndrome represents about 10% of the indications of oocyte donation. Pregnancy rates are as satisfactory as for other indications when endometrial preparation is sufficient. Unfortunately patients with Turner syndrome present somatic abnormalities inducing obstetrical complications and even an elevated mortality rate, in particular by aortic dissection. So, it is absolutely necessary to define with extreme precision the elements of medical check up previous to oocyte donation as well as the forms of medical care during pregnancy which would protect the patients from severe complications.

Clinical and epidemiological description of aortic dissection in Turner's syndrome

BACKGROUND

Women with Turner's syndrome have an increased risk of congenital cardiac malformations, ischaemic heart disease, hypertension and stroke. Aortic dissection seems to occur with increased frequency.

AIM

To describe in more detail aortic dissection as encountered in Turner's syndrome, giving attention to clinical, histological and epidemiological aspects.

MATERIALS AND METHODS

Based on a retrospective study, we describe the clinical, karyotypic, and epidemiological aspects of aortic dissection as encountered in cases of Turner's syndrome seen in Denmark and Sweden.

RESULTS

The median age at onset of aortic dissection in 18 women was 35 years, ranging from 18 to 61 years. Fourteen of 18 women had a 45,X karyotype, while 2 patients had 45,X/45,XY, and 2 had the 45,X/46,X+r(X) complement, respectively. Echocardiography was performed in 10 of 18 patients before their acute illness, and showed signs of congenital cardiac disease, with either bifoliate aortic valves, dilation of the aortic root, or previous aortic coarctation evident in most patients. In 5 patients evidence of a bifoliate aortic valve was conclusive. Hypertension was present in 5 of 18 patients, while 10 of the patients died from aortic dissection, of so-called type A in 6, type B in 3, while in the final case the origin of dissection could not be determined. Biochemical analysis showed altered ratio between type I and type III collagen. Histology showed cystic medial necrosis in 3 of 7 cases. We estimated an incidence of dissection of 36 per 100,000 Turner's syndrome years, compared with an incidence of 6 per 100,000 in the general population, and a cumulated rate of incidence of 14, 73, 78, and 50 per 100,000 among 0-19, 20-29, 30-39, and 40+ year olds, respectively.

CONCLUSION

Aortic dissection is extremely common in the setting of Turner's syndrome, and occurs early in life. Patients with Turner's syndrome should be offered a protocol for clinical follow-up similar to that provided for patients with Marfan syndrome, and each clinic should embrace a programme for follow-up.

[Turner's syndrome and oocyte donation]

This paper reviews literature about oocyte donation for patients with Turner's syndrome and reports the experience of our center. Before contemplating pregnancy, it is essential to perform a careful evaluation of the cardiovascular system, the renal system, the thyroid status and the glucose tolerance. Different studies have reported a suboptimal response of the endometrium of women with Turner's syndrome to oestrogen therapy, and suggested that higher doses of estrogens may be necessary to achieve appropriate endometrial preparation. Pregnancy rate per transfer following oocyte donation is around 30% for patients with Turner's syndrome, comparable to the one observed for patients with other conditions requiring oocyte donation. Miscarriage rate is however higher (40-50%) after oocyte donation in Turner's syndrome, and could be related to the presence of a hypoplastic uterus along with hypovascularization. During pregnancy, cardiovascular complications are potentially the most severe, such as the exacerbation of a preexisting hypertension and the dissection of aortic aneurysms. There is a high rate of Caesarean section among Turner's syndrome patients, the main reason being fetopelvic disproportion. Regarding the increased obstetrical risks in Turner's syndrome patients, the selective transfer of one embryo should ideally be performed in order to avoid additional risks associated with multiple pregnancies. In our center, 9 patients with a Turner's syndrome had 15 cycles of oocyte donation. Five pregnancies were obtained among which three were evolutive. The outcome of oocyte donation cycles were comparable for patients with a Turner's syndrome and for patients with other indications of oocyte donation.

Turner's syndrome in adulthood

Turner's syndrome is the most common chromosomal abnormality in females, affecting 1:2,500 live female births. It is a result of absence of an X chromosome or the presence of a structurally abnormal X chromosome. Its most consistent clinical features are short stature and ovarian failure. However, it is becoming increasingly evident that adults with Turner's syndrome are also susceptible to a range of disorders, including osteoporosis, hypothyroidism, and renal and gastrointestinal disease. Women with Turner's syndrome have a reduced life expectancy, and recent evidence suggests that this is due to an increased risk of aortic dissection and ischemic heart disease. Up until recently, women with Turner's syndrome did not have access to focused health care, and thus quality of life was reduced in a significant number of women. All adults with Turner's syndrome should therefore be followed up by a multidisciplinary team to improve life expectancy and reduce morbidity.

Turner syndrome and the heart: cardiovascular complications and treatment strategies

Turner syndrome is a condition usually associated with reduced final height, gonadal dysgenesis, and thus insufficient circulating levels of female sex steroids, and infertility. A number of other signs and symptoms are seen more frequently with the syndrome. With respect to cardiac function, congenital malformations of the heart and the great vessels, hypertension and ischemic heart disease, and increased risk of aortic dissection are all conditions that the pediatrician or the physician caring for females with Turner syndrome should keep in mind. Many girls and adolescents with Turner syndrome receive growth hormone (GH) treatment, which has so far been an effective and well-tolerated therapy. Nevertheless, because of the experience from acromegaly, the physician should monitor blood pressure and perform echocardiography, together with clinical examinations by a cardiologist at regular intervals. During adulthood most women with Turner syndrome are faced with premature menopause and the need for female hormone replacement therapy (HRT). During clinical evaluation of girls and women with Turner syndrome, these conditions and complications should be kept under surveillance. Here the cardiovascular complications of Turner syndrome are reviewed. The risk of congenital heart defects such as bicuspid aortic valves, aortic coarctation, other valve abnormalities, and septal defect is increased. Likewise, the risk of aortic dissection at a young age is increased, as is the risk of hypertension, ischemic heart disease, and stroke. GH therapy does not seem to adversely affect the heart, although longer-term follow-up studies are needed. In short-term studies, HRT lowers blood pressure, while any effect on the risk of ischemic heart disease has not been evaluated. Treatment with GH and HRT are discussed in relation to the heart and great vessels. Presently, the pathophysiology of the congenital cardiovascular malformation in Turner syndrome is unexplained, although different theories exist. Recommendations for clinical practice are given, including life-long surveillance of cardiac function, aortic diameter and blood pressure.

Evaluation and management of infertility in women: the internists' role

Interventions for infertility have greatly increased in number and sophistication. Women with multiple medical problems and women near or beyond menopause are now able to conceive. The internist will be called on to assess the risk that infertility interventions pose and to counsel patients accordingly. Knowledge of the medical illnesses associated with infertility, the types of infertility treatments available, and the medical complications of these interventions are required to properly assess this risk. Medical complications of infertility interventions can be direct effects of related drugs and technologies and indirect consequences of the induced pregnancy, multiple gestation, or associated medical conditions. This article reviews the definitions and scope of infertility, the interventions used for treatment of infertility, the medical complications of these interventions, the potential risks of fertility treatment in women unable to conceive spontaneously, and important issues for preconception counseling.

Further delineation of aortic dilation, dissection, and rupture in patients with Turner syndrome

OBJECTIVE

Although cardiovascular malformations (CVMs) are well-recognized congenital anomalies in Turner syndrome, aortic dilation and dissection are less common and less familiar. Most of the relevant literature is limited to single cases reports or small series. We sought to increase the information available about the frequency and characteristics of aortic dilation in patients with Turner syndrome.

DESIGN

A 1-page survey of cardiac abnormalities, including aortic dilation, was mailed to approximately 1000 (1040 verified) members of the Turner Syndrome Society as an enclosure in the June 1997 newsletter. We also conducted a literature review.

PARTICIPANTS

A total of 245 patients or families of patient members of the Turner Syndrome Society responded to the survey ( approximately 24% response rate).

RESULTS

A CVM was reported in 120 of 232 (52%) respondents to this questionnaire. Obstructive lesions of the left side of the heart predominated and included bicuspid aortic valve (38%) and coarctation (41%). Aortic dilation was reported in at least 15 of 237 respondents (6.3%; 95% confidence interval: 3.6%-10.3%); 2 of 15 (13%) had dissection. Twelve of 15 (80%) patients had an associated risk factor for aortic dilation such as a CVM or hypertension. The 3 (20%) patients who did not have a CVM or hypertension were all younger than 21 years. In the entire group with aortic dilation, 10 of 15 (67%) patients were younger than 21 years. All patients with aortic dilation had involvement of the ascending aorta, and 2 had additional involvement of the descending aorta distal to a repaired coarctation. An update of the literature revealed 68 patients with aortic dilation, dissection, or rupture. An associated CVM or hypertension was reported in 53 of 59 (90%) informative patients. At least 6 (10%) had no predisposing risk factor (information was inadequate for 9 of 68 patients). The following patterns of aortic involvement were identified: ascending +/- descending aorta with coarctation (14); ascending +/- descending aorta without coarctation (39); descending aorta with coarctation (3); descending thoracic or abdominal aorta without coarctation (4); and unspecified (8). Dissection or rupture was reported in 42/68 (62%). Two reported patients died suddenly from aortic dissection in the third trimester of assisted pregnancy. At least 20 (29%) patients were younger than 21 years. One of the 6 (17%) patients with isolated aortic dilation was in this younger group.

CONCLUSIONS

More information is needed about the frequency and natural history of aortic dilation in Turner syndrome. This work contributes new patient data and increases the literature review. Despite the well-recognized limitations of self-reporting, this survey detected aortic dilation with or without dissection in approximately 6% of patients with Turner syndrome. Although rare, this is a potentially catastrophic occurrence, warranting greater awareness among health professionals. In this study and the literature, the vast majority of patients with aortic dilation have an associated risk factor such as a CVM, typically bicuspid aortic valve or coarctation, or systemic hypertension. These patients represent a higher risk group that should be followed appropriately, usually under the direction of a cardiologist. Patients undergoing assisted pregnancy also should be evaluated closely. It is generally accepted that at the time of diagnosis of Turner syndrome, all patients should have a complete cardiology evaluation including echocardiography. The small number of patients with aortic dilation without a CVM, who would not be under the long-term care of a cardiologist, makes it prudent to screen all patients with Turner syndrome for this potentially lethal abnormality. The specific timing for this screening is controversial. Our recommendations for prospective imaging do not represent a rigid standard of care.